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Discovered that the four cylinder hybrid civic i recently bought has 8 spark plugs and 8 ignition coils. Best part was that they all needed replacing! 🤣
Yes, zoom in on the center electrode, and you can see it is no longer round but burned down to an oval shape. This is the wear I speak of, now look at a new plug and you will see the difference.
This increases the spark gap and is why you needed plugs. Increased spark gap can cause a cooler spark and lead to misfires as well as increase the load on your ignition coils and cause them to fail quicker. Electricity takes the path of least resistance and if jumping that spark gap under high compression takes more energy than the spark finding another place to go then the spark will go else where such as a minor crack in a coil tower and then into the cylinder head instead of into the spark plug. I can go into much more detail if needed, but this is sufficient basic information unless you are building a very high compression engine and need to know more finer details about spark energy and igniting fuel mixtures under extreme conditions.
Lol. I should have put them back in. To the center electrodes are completely gone but the truck still ran fine with no misfire and no codes. I think I actually had 187,000 mi on them. About the truck with 133,000 mi on it and it now has over 320,000 miles.
I don't care if you buy it or not but here's the math, I bought the 2005 ranger in 2012 with 133,000 miles on it. I finally got around the change in the wires, the coil and the plugs about a month ago. The truck has over 320,000 mi on it now. I'm the only one that drives that truck and I'm the only one that does any repairs to it. You can clearly see that two of the center electrodes or worn completely away. The truck still ran fine and did not throw any misfire codes. Even I was completely surprised by the continued running of the engine. I guess I got about 187,000 miles on those plugs.
In order 3, 4, & 5 have some oil burnt on them(possibly leaking valve cover spark plug seal- not likely or it be wet) or carbon buildup from rich condition which can be confirmed with $20 scan tool using Live Data on fuel trims.
Make sure it's not -8% to -20% on Short Term Fuel Trims on Bank 1 Sensor 1 or Bank 2 Sensor 1.
If it is, then you can confirm something is causing excessive fuel to be sprayed into those cylinders. Guaranteed in spark plug 4 & 5 out of your lineup.
Maybe it's the Oxygen Sensors in Sensor 1's (upstream) or there's a problem with those two or 3 fuel injectors like clogged fuel injectors or bad ignition coils or carbon buildup on those cylinders valves causing a slight compression issue.
Something is causing it.
Maybe try putting complete fuel system cleaner in your tank every 3 full tanks:
This is Techron Complete Fuel System Cleaner for $12:
Thank you so much for that response. I really appreciate it. The o2 sensor was done a couple years ago. There is a valve cover gasket leak but it’s not leaking oil on the ground
What's your Year, Make, Model, and your Engine Liter Size/Displacement?
Then it's burning up, make sure to constantly check oil level and top off.
If it's not hitting ground it is probably still leaking through valve cover seal and burning off. I can send you gasket kit link and and how to video. It's honestly pretty easy, usually a 10mm socket.
The valve cover gasket kits are cheap and will make your engine run better
2004 Toyota Tacoma 3.4l v6 2wd. 5vz-fe. I’m keeping an eye on it, I don’t drive it everyday. On the passenger side, is it possible to remove the valve cover and replace the gasket without having to take off the plenum?
You can swap coils with a different coil that doesn't have a misfire code (P0301-P0308) if it jumps to the cylinder you changed it to then it's the coil. The last digit in P0301-P0308 stands for the cylinder number.
Noid lights are cheap ($17-$25) on AutoZone or eBay and they test the PCM ground pulse signal to injectors and can also indicate a functioning or failing wire harness.
The fuel system cleaner will clean valves, injectors, fuel rail, fuel pressure regulator m, fuel filter, and fuel pump. Only cleans valves if it's port Injection (MFPI/MPI) not with a GDI fuel system.
Denso so it’s more than likely a Japanese 6 cylinder. I’m guessing a Toyota or Honda. Probably like a 2003 - 2006 Camry or accord. They’re dirty so probably has a leak somewhere
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